Table 1. Consensus instructions for assessing ultrasonographic features of polycystic ovaries. Counting ovarian follicles  When counting follicles throughout the entire ovary, scroll through the digital recording using the frame-by-frame feature.  Count a single sweep through the ovary multiple times to generate a consensus count.  When counting follicles in a single plane, adjust contrast to improve visibility/conspicuity of follicles.  Most follicles will appear as round anechoic areas but some follicles (i.e. particularly, those atretic) will appear irregularly shaped or compressed.  Consider that discernible walls may not be apparent between adjacent follicles.  Use artifacts of specular reflection to aid in the identification of follicles.  Do not count the cystic cavity of the corpus luteum as a follicle. Measuring the largest follicle diameter  Convince yourself by scrolling back and forth through the digital recoding that the follicle you have chosen is a single follicle.  Freeze the recording at the frame which represents the largest cross-sectional area of the follicle in question.  Adjust contrast and enlarge the image.  The first linear measurement should be that of the largest longitudinal plane.  Draw your line keeping in mind that the follicle wall should be included in the measurement as well as any area of acoustic artifact.  The second linear measurement is that which bisects the first line at a right angle.  The mean of these two lines represents the Largest Follicle Diameter.  Make largest follicle measurements for both image clips and report the largest of the two.  Do not count the corpus luteum as the largest follicle. Calculating ovarian volume and identifying follicle distribution pattern  Convince yourself by moving back and forth through the digital recording that you recognize the limits of the ovary.  Freeze the recording at the frame which represents of the largest cross-sectional area.  Decide on the follicle distribution pattern in this cross-section (i.e. peripheral or even).  If this image contains a follicle ≥10mm or a large cystic CL, designate the follicle pattern as other. Draw your line keeping in mind that small round anechoic areas may lie outside the ovarian capsule (i.e. small vessels that should not be confused as follicles) and that an area of acoustic artifact may be present.  The second linear measurement should represent the widest plane of the ovary and should cross the longitudinal measurement at a right angle.  Repeats these measurements for the second clip and use the averages of the longitudinal and antero-posterior measurements to calculate volume. Identifying corpora lutea  A corpus luteum may appear as a large cystic structure or a smaller hyperechoic structure with a small to negligible fluid-filled cavity.  Walls of the corpus luteum are generally thick, hyperechoic and crenulated.  The cystic cavity of a corpus luteum generally has heterogeneous areas of echogenicity.  Ensure that you can identify the corpus luteum in both image clips before deciding on its presence.